TOKYO, Dec. 28 (Xinhua) -- Japan's core consumer price index fell 0.5 percent from a year earlier in November, according to data released by the Ministry of Internal Affairs and Communications on Tuesday.

The drop in prices shows that the nation is still struggling to get to grip with crippling deflation and November marks the 21st straight month consumer prices have logged a downward trend, the ministry said.

Consumer prices, excluding fresh food, fell 0.5 percent from a year earlier, slightly higher than the median market forecast for a 0.6 percent retraction on year.

Core CPI for the Tokyo metropolitan area -- a leading gauge of national price trends -- declined 0.4 percent in December, according to the government data. This follows a 05 percent retraction in November and was in line with economists' expectations.

CPI is a measure estimating the average price of consumer goods and services purchased by households. A consumer price index measures a price change for a constant market basket of goods and services from one period to the next within the same area, city, region, or nation.

The index is determined by measuring the price of a standard group of goods meant to represent the typical "market basket" of a typical urban consumer.

There may well be further pressure exerted on the Bank of Japan (BOJ) to do more to tackle deflation henceforth as part of its " comprehensive monetary easing package" unrolled in October.

The BOJ board forecast in October core prices will rise 0.1 percent next fiscal year and 0.6 percent the following year.